RAID 6 is made up of block-stage striping with double dispersed parity. Double parity gives fault tolerance up to 2 unsuccessful drives. This helps make much larger RAID teams more practical, especially for superior-availability units, as massive-ability drives get lengthier to restore. RAID 6 involves no less than four disks. https://raid19853.blognody.com/26357349/raid-for-dummies